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Don Marolf paper

  1. Oct 15, 2004 #1
    From the Eire conference:http://arxiv.org/abs/hep-th/0410168

    Interesting concept for Observer Dependent Entropic States.
  2. jcsd
  3. Oct 15, 2004 #2
    Some obvious consequence paramiters must be re-gauged for say..the Hubble far-wide deep field images?

    Are we 'instrumental', in dictating what images are recieved from far away (b-h) Horizons, by an Entropic "OBSERVABLE", Function?
  4. Oct 15, 2004 #3
    The text mentions the Covariant entropy bound; it got me confused as i never heard of such a bound, but then looking the references i realized that is an alternative name for Bousso's bound, that I've found always interesting. Would be nice if Bousso's conjecture can be proven
  5. Oct 15, 2004 #4


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    for explicitness, this exerpt
    ---quote from Marolf abstract---
    ...a new sense [3] in which the entropy of an “object” depends on the observer making the measurement, so that observers crossing the horizon measure a different entropy flux across the horizon than do observers remaining outside.
    ---end quote---

    and he cites a 2003 paper by him and two others about this
    3. D. Marolf, D. Minic and S. F. Ross, arXiv:hep-th/0310022.
    so if one wanted to follow up on the observer-dependence of entropy one might check out

    for some people here it may be obvious that entropy is going to depend majorly on the observer---if someone does have a good grasp of this it would be great to have some explanation/clarification. meteor? sA? anybody?
  6. Oct 15, 2004 #5
    Do you suppose all those entropy calculations for black holes applies equally to the cosmological horizon which is also has accelerated mass that becomes invisible?
  7. Oct 15, 2004 #6


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    You may find this of interest
    This paper has 79 citations, so it apparently has been well received.
  8. Oct 17, 2004 #7
    marcus, I read the link you gave and Marolf proposes there also the idea of observer dependent entropy. He says that in a Minkowski space, had you some localized matter in some part of it, and being the space completely void apart of the matter and two observers, the inertial observer will measure a different entropy for the matter than the Rindler observer (a Rindler observer is an observer in Minkowski space undergoing constant acceleration)
    I cannot give many much insight about it, as the math is a bit beyond me, i think I'm going to try to improve my knowledge of the Unruh effect, that always has seemed me somewhat misterious
    Last edited: Oct 17, 2004
  9. Oct 17, 2004 #8
    It does seem that they are indeed applying the entropy of area calculations to the cosmological horizon. What I have to wonder is how would they know how much matter has already disappeared behind the horizon? And how is this consistent with the horizon getting smaller as more matter falls behind the cosmologcial horizon? Shouldn't the horizon be getting larger as more mass falls behind it?
  10. Oct 17, 2004 #9
    Me and Self A discussed this on another forum 2yrs ago, this is his reply:


    there were mitigating circumstances to my reasoning then, as still is the case today, the Laws of Physics and the Law of Observation vary, QM has a differing viewpoint from SR/GR, if one measures 'something' locally, then an observer measuring the same something further away will have to contend that there are differing laws regarding information recieved.

    A simple example is a local measurement of a specific single Photon, this cannot be correlated by a measurer that is not local, in the paper I linked by Marolf, this equates to a Far away observer registering an Electron Positron emission, in response to a single photon crossing the Event(local) horizon near a Blackhole, 2 for 1 !
  11. Oct 19, 2004 #10
    Last edited: Oct 19, 2004
  12. Oct 23, 2004 #11


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  13. Oct 25, 2004 #12
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